https://datatracker.ietf.org/doc/draft-ietf-tls-esni/
https://www.cloudflare.com/ssl/encrypted-sni/

https://support.mozilla.org/en-US/kb/understand-encrypted-client-hello
https://blog.mozilla.org/en/products/firefox/encrypted-hello/

2023
https://www.opennet.ru/opennews/art.shtml?num=59869